The present invention relates to a novel tape cassette and, more specifically, to a large tape cassette to be used on a recording/reproducing apparatus capable of using both a large tape cassette and a miniature tape cassette. The present invention is intended to enhance the dustproof performance and the strength of a large tape cassette having exclusive locating contact protrusions other than the locating contact protrusions common to a miniature tape cassette.
There is known a recording/reproducing apparatus capable of using both a large tape cassette and a miniature tape cassette, that is, the so-called compatible recording/reproducing apparatus.
Such a recording/reproducing apparatus are designed so as to use as many members and devices common to a large tape cassette and a miniature tape cassette as possible to simplify the construction thereof.
For example, recesses, i.e., mouths into which a tape driving member is inserted when the tape cassette is loaded into a recording/reproducing apparatus, of substantially the same size are formed respectively in the large tape cassette and the miniature tape cassette to use the same tape driving member in the same operating mode for driving the recording tapes of both the large tape cassette and the miniature tape cassette.
FIG. 15 shows, in a superposed view, a large tape cassette a and a miniature tape cassette b respectively having mouths c and d of substantially the same size to be used on such a recording/reproducing apparatus.
Some compatible recording/reproducing apparatuses are provided with common locating lugs to be used for both locating the large tape cassette a and locating the miniature tape cassette b.
When the miniature tape cassette is to be used on such a recording/reproducing apparatus, the miniature tape cassette must be provided with locating contact protrusions in ranges e.
Naturally, the large tape cassette a also must be provided with locating contact protrusions in the ranges e to use the common locating lugs.
However, as regards the large tape cassette a, it is preferable, in view of stable locating, that locating contact protrusions of the large tape cassette a to be brought into contact with locating lugs are separated from each other by a comparatively large distance and hence it is preferable to separate the locating contact protrusions of the large tape cassette a by a largest possible distance from each other when the large tape cassette a is used on a recording/reproducing apparatus designed for using only the large tape cassette a. Accordingly, the locating contact protrusions of the large tape cassette &lt;a&gt; are formed in ranges f.
The tape cassette is provided with a lid to protect an exposed portion of the recording tape contained therein.
If the locating contact protrusions are covered with the lid assembly, the tape cassette cannot be located with the lid assembly positioned at its closed position for covering the front side of the recording tape. Therefore, as shown in FIG. 16, a recess h is formed in a lid q so as to receive a locating contact protrusion i in the recess h so that the locating contact protrusion i is exposed to enable the tape cassette to be located with the lid q positioned at its closed position.
In such a structure, however, a gap is formed between the locating contact protrusion i and the upper edge of the recess h to deteriorate the dustproof capability of the tape cassette, if the lid q is moved even slightly toward the open position. If the locating contact protrusions are formed over the wide ranges f as in the conventional large tape cassette a, a gap is formed in a wide range when the lid q is slightly opened, which deteriorates the dustproof capability of the tape cassette significantly.
Since portions of the lid q other than those in which the recesses h are formed are not supported from behind by the case of the tape cassette, the lid q is flexed easily backward when a pressure is applied thereto. If such portions are formed in the wide ranges f, the strength of the lid q is reduced greatly.